Wood burning, water heating stove

ABSTRACT

The invention consists of a cylinder within a cylinder with the inner cylinder acting as the firebox while the outer cylinder is the water tank. The top of the inner cylinder exceeds the height of the outer cylinder and consists of a top lid through which wood is introduced. An air blower is specially cofigured to create a vortex of air which feeds the fire.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the invention

[0002] This invention relates generally to wood burning stoves but more particularly to an immersion stove that heats water.

[0003] 2. Background

[0004] Wood burning stoves used for heating water have been around for a long time, starting with the agricultural boilers of the 19th century. One example is of an immersion stove is U.S. Pat. No. 251,518 by Bryden which discloses a wooden tub inside of which is a wood burning stove, in this manner, most of the heat emanating from the iron stove serves to heat up the water. Other immersion units, large and small, have been patented over the years. U.S. Pat. No. 4,360,003 by Hardy features a coil placed within the hot water reservoir to supply hot water to the faucets in a dwelling while the hot water from the tank is used for heating purposes.

[0005] A prior art brochure from the company “Central boiler” explains in detail how hot water can be used in a central heating system, whether that central heating system is a forced air system water heated system. Also the stove from that same company, which is very similar to the stoves that are seen in U.S. Pat. No. 6,029,648 by Willis, U.S. Pat. No. 4,461,242 by Black and even U.S. Pat. No. 4,360,003 by Hardy features an optional fuel injector making that stove a hybrid stove capable of using oil, natural gas or propane.

[0006] U.S. Pat. No. 4,944,286 by Millington and U.S. Pat. No. 6,397,833 by Jarvi show two examples of stoves where the solid fuel, generally pellets, is fed from the top by opening a top lid or cover. Most of the more recent patents feature a forced air intake by way of an electric fan to control the rate of burning.

[0007] Generally, the fan is connected to a thermostat which starts or stops the fan as required. Other indicators are quite common such as when it is time to refill with fuel when the temperature of the water falls below a certain temperature or the inside of the combustion chamber falls below a certain temperature.

[0008] Finally, U.S. Pat. No. 6,036,475 describes a fan combined with a fuel injector to create a cyclonic effect so that the flame clings to the walls of the combustion chamber, thus more effectively transferring the heat into the adjoining water tank.

[0009] Most of these stoves are rather big and bulky and requires the smelting cutting and machining of expensive steel that can take repeated expansion and contraction from the temperature variations. Because of these factors, these stoves are quite expensive and may not be considered by many as a possible alternative to more mainstream means of central heating and water heating. Even more so for heating water for swimming pools or hot tub where such These stoves because of these drawbacks, it is easily understood that such types of trims are less than ideal and that an alternative must be found.

SUMMARY OF THE INVENTION

[0010] The invention consists of a cylinder within a cylinder with the inner cylinder acting as the firebox while the outer cylinder is the water tank. The top of the inner cylinder exceeds the height of the outer cylinder and consists of a top lid through which wood is introduced. Because cylinders are easy to manufacture and require few solder points, it is possible to economically produce this stove.

[0011] The foregoing and other objects, features, and advantages of this invention will become more readily apparent from the following detailed description of a preferred embodiment with reference to the accompanying drawings, wherein the preferred embodiment of the invention is shown and described, by way of examples. As will be realized, the invention is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.

BRIEF DESCRIPTION OF THE PREFERRED EMBODIMENT

[0012]FIG. 1a cross sectional side view of the wood burning, water heating stove.

[0013]FIG. 1b front view detail of the air outlet.

[0014]FIG. 2a side elevation of a wood burning, water heating stove.

[0015]FIG. 2b side elevation detail of the top lid opened.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0016] A wood burning, water heating stove (10) has an inner cylinder (12) and an outer cylinder (14). The inner cylinder (12) is a firebox (22) and the outer cylinder (14) is a water tank (20). The top of the inner cylinder (12) exceeds the height of the outer cylinder (14) and consists of a top lid (24) through which wood is introduced.

[0017] A blower (26) connected to a conduit (28) blows air inside the firebox (22) where it exits by an air outlet (30) which is angled so as to project the air tangentially to the inner wall of the inner cylinder (12) to induce a rotational flow which creates a vortex to evenly stimulate the fire. The smoke (58) rises up towards a plate (32) which provides a detour before reaching a chimney (34) so that there can be a secondary burning which reduces the amount of pollutants, creates and maintains more heat inside the firebox (22).

[0018] Surrounding the chimney (34) is a double wall (36) which preheats outside air (38) which then passes through a preheated air conduit (40) before it enters the blower (26).

[0019] There are a number of elements which are to be expected such as a cold water inlet pipe (42) and hot water loutlet pipe (44), a water refill inlet (46) a water level gauge (48). An additional feature is a coil (50) which can be used to heat water for a spa and standard electric water tank heating elements (not shown) in case wood burning is not used to keep the water hot. Additionally, the blower (26) can easily be replaced by an oil or gas blower burner with the burner being situated at the outlet (30).

[0020] Referring more particularly to FIG. 2a, in order to keep the water (52) warm a layer of insulation (18) surrounds the outer cylinder (14) and is itself covered by a shell (16) which provides the finished look to the wood burning, water heating stove (10). FIG. 2b shows how the lid opens to allow the introduction of wood. The bottom of the firebox (22) can easily be cleaned of its ashes by using a ladle or such implement.

[0021] The air outlet (30) has a first angle (29), and a second angle (31), and an opening (33). The air exits the opening (33) by hitting a bottom wall (35) which has the combination of the first and second angle (29, 30) this biases the air towards the inner wall of the inner cylinder (12). After the air has completed the circumference it hits the outside of the bottom wall (35) and is directed away from the wall of the inner cylinder (12) and draws some of the outcomiong air from the air outlet (30) with it. This brings some air closer to the center of the inner cylinder (12) in an inwardly spiraling motion which is part of the vortex. 

1. A wood burning, water heating stove comprising: an inner cylinder and an outer cylinder, said inner cylinder being a firebox and said outer cylinder being a water tank; a top lid extending from the top of said inner cylinder allowing for input of wood; a blower connected to a conduit leading to an air outlet; said outlet being angled so as to create a vortex;
 2. A wood burning, water heating stove such as claim 1 wherein: a plate provides a detour before reaching a chimney;
 3. A wood burning, water heating stove such as claim 1 wherein: said chimney further provided with a double wall to preheat outside air passing through a preheated air conduit leading to said blower.
 4. A wood burning, water heating stove such as claim 1 wherein: said air outlet having a first angle, and a second angle, and an opening; air exiting said opening hitting a bottom wall thus biasing air tangentially along inner wall of said inner cylinder; air having completed the circumference hitting outside of said bottom wall and directed away from wall of said inner cylinder, drawing some outcomiong air from said air outlet to create an inwardly spiraling motion part of a said vortex. 